We move on to an incredible story. A 37-year-old ohio man who came back from the dead. His heart stopped for 45 minutes. The doctors finally gave up. But his son simply would not. Abc's alex perez has his unbelievable story. Reporter: It's the miracle tony yahle doesn't understand. But will never forget. I didn't realize anything was wrong. Reporter: He said his evening began just like the rest. I went to bed like normal last night. Didn't have any idea anything was wrong. Reporter: Neither did his wife, melissa, until she woke up in the morning. I could tell his breath breathing was off. Tried to revive him. He would not wake up. Reporter: In a panic, the family called the ambulance and rushed to the hospital. Doctors searching for the problem. They anticipated they would find a heart blockage. The doctor came out and said they could not find any blockages in his heart. Reporter: Through the day, medical teams couldn't figure out what was wrong with tony. Then, in the afternoon, his heart stopped beating. And for 50 minutes, stayed that way. The doctors scrambled to revive him. To no avail. With very heavy hearts, we had to stop. And we pronounced him dead. Reporter: For tony's daughter, kirsten, it was simply too much to bare. I felt like pieces of my heart had been ripped out. Reporter: As nurses were preparing to take tony to the morgue, tony's son, lawrence, with a pastor by his side, stood right in front of his dead father. He began talking to him. Refusing to accept what doctors had told them. I said, dad, you're not going to die today. Reporter: Then, came something science can't seem to explain. Took about three steps. And my pastor, he got my attention. He said, lawrence, there's a heartbeat. Reporter: On the lone heart monitor still attached to him, a flutter. Tony's heart started beating again. The greatest thing in the world, after we were told he was gone, pronounced dead, he has a heartbeat. Even the doctors agree it's a miracle. Reporter: Tony says he has no memory of what happened. He has a pacemaker and a defibrillator. But his heart seems normal. Especially for a man who seems to have returned from the dead. No one has an exprenation. But I had a lot of people praying for me. And god moved that day. Reporter: For "good morning america," alex perez, abc news, chicago.

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